Ep 6. The Fabric of the Cosmos: Illusion of Time

In NOVA season 39 episode 6, titled "The Fabric of the Cosmos: Illusion of Time," host and physicist Brian Greene explores the concept of time and its perception. Greene delves into the idea of time as a physical entity and how it shapes our understanding of the universe, asking questions like "What is time?" and "Is time travel possible?"

The episode starts off by examining how time is perceived differently by individuals, depending on their location and the speed they are moving. Greene introduces the idea of time dilation, a phenomenon explained by Einstein's theory of relativity, where time appears to slow down for objects moving at high speeds or in strong gravitational fields. This sets the stage for a journey through the science of time.

Next, Greene sets out to explore the fundamental nature of time. He interviews various scientists, including physicist Lee Smolin, who suggests that time could be a fundamental aspect of the universe rather than an illusion. Greene also discusses the idea of entropy, which measures the disorder of a system. Entropy, according to Greene, is intimately linked with the arrow of time, or the perceived directionality of time that moves from past to future.

The episode then delves into the history of timekeeping, from the sundial to the atomic clock. Greene explains how the measurement of time has become increasingly precise over the centuries, from the development of pendulum clocks to the use of cesium atomic clocks. He also discusses how the advent of worldwide communications and global positioning systems depend on the precise measurement of time.

Greene also explores the nature of time in the context of the universe. He discusses the Big Bang theory and how it presents a unique challenge to our conceptions of time. According to the Big Bang model, time as we know it began with the creation of the universe. However, Greene explains how the theory also predicts the possibility of other universes, each with its own measures of time.

Finally, Greene tackles the idea of time travel and whether it is possible. He examines the various philosophical and scientific implications of time travel, including the possibility of altering the past and creating paradoxes. Greene also speculates on potential methods for time travel, from wormholes to the manipulation of black holes.

Throughout the episode, Greene uses colorful analogies and visual aids to explain complex concepts in a way that is accessible to viewers. His passion for the topic is evident, as he takes on the challenge of explaining an intangible concept in an engaging and informative way.

In conclusion, "The Fabric of the Cosmos: Illusion of Time" is a fascinating exploration of one of the most elusive concepts in science. Brian Greene's enthusiasm for the subject is infectious, and his explanations leave viewers with a newfound appreciation for the complexity of time and its role in our understanding of the universe.